US4022622A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dispersing polymeric particles in aqueous medium for coating silver halide emulsion layers
Assignee: Agfa Gevaert NV
•
Filing: 1976-03-01
•
Granted: 1977-05-10
•
Expires: 1996-03-01
Abstract
Abstract Polymeric particles are homogeneously dispersed in aqueous medium by a process which comprises dissolving a water-insoluble film-forming polymer in a water-insoluble, ethylenically unsaturated monomer which is liquid at room temperature. The solution formed is dispersed by stirring in an aqueous solution of a hydrophilic colloid and of a dispersing agent, stirring being continued until a stable dispersing of polymer-in-monomer solution droplets having a diameter between 1 and 10 microns, preferably between 1 and 6 micron, in said aqueous solution is obtained. While continuously stirring the dispersion in the presence of a free-radical forming polymerization initiator, the dispersion is heated at the decomposition temperature of said polymerization initiator to effect polymerization of the water-insoluble, liquid monomer and to form an aqueous dispersion of solvent-free polymer particles. The homogeneously dispersed polymer particles are used in hydrophilic coating compositions as matting agents, particularly in protective layers for photographic materials formed of these hydrophilic coating compositions.
Inventors
- 👤 Daniel Maurice Timmerman
- 👤 Victor Jan Thijs
- 👤 Walter Frans De Winter
- 👤 Frans Henri Claes
- 👤 Hubert Vandenabeele
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:58
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/95; C; C08; C08J; C08J3/00; C08J3/02; C08J3/03; C08J3/07; C08J3/12; G03C1/005; G03C1/06; G03C1/32; G03C1/7614; Y; Y10; Y10S; Y10S430/00; Y10S430/1053; Y10S430/1055; Y10S430/114; Y10S430/117; Y10S430/151
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
218 words
Light-sensitive photographic materials comprising a support, a light-sensitive silver halide emulsion layer and a water-permeable protective layer exteriorly to said emulsion layer, said protective layer being formed from a hydrophilic coating composition containing an aqueous binder solution and a homogeneous aqueous dispersion of polymer particles, said dispersion prepared by dissolving a water-insoluble, film-forming polymer in a water-insoluble ethylenically unsaturated monomer which is liquid at room temperature to provide a solution thereof, dispersing by stirring the solution thus formed in an aqueous solution of a hydrophilic colloid and dispersing agent, the stirring being continued until a stable dispersion of polymer-in-monomer solution droplets having a diameter between 1 and 10 micron is formed in said aqueous solution and, while continuously stirring in the presence of a free-radical forming polymerization initiator, heating the dispersion to the decomposition temperature of said polymerization initiator to effect polymerization of said water-insoluble liquid monomer and to form an aqueous dispersion of solvent-free polymer particles, said unsaturated monomer being selected so as to be a solvent at room temperature for said film-forming polymer, and to provide upon said polymerization in the presence of said film-forming polymer, polymer particles having a glass transition temperature of at least 60° C., and said binder of said aqueous binder solution when in an aqueous solution being compatible with said dispersion.
Claim 2
Dependent Claim
218 words
Light-sensitive photographic materials comprising a support, a light-sensitive silver halide emulsion layer and a water-permeable protective layer exteriorly to said emulsion layer, said protective layer being formed from a hydrophilic coating composition containing an aqueous binder solution and a homogeneous aqueous dispersion of polymer particles, said dispersion prepared by dissolving a water-insoluble, film-forming polymer in a water-insoluble ethylenically unsaturated monomer which is liquid at room temperature to provide a solution thereof, dispersing by stirring the solution thus formed in an aqueous solution of a hydrophilic colloid and dispersing agent, the stirring being continued until a stable dispersion of polymer-in-monomer solution droplets having a diameter between 1 and 10 micron is formed in said aqueous solution and, while continuously stirring in the presence of a free-radical forming polymerization initiator, heating the dispersion to the decomposition temperature of said polymerization initiator to effect polymerization of said water-insoluble liquid monomer and to form an aqueous dispersion of solvent-free polymer particles, said unsaturated monomer being selected so as to be a solvent at room temperature for said film-forming polymer, and to provide upon said polymerization in the presence of said film-forming polymer, polymer particles having a glass transition temperature of at least 60° C., and said binder of said aqueous binder solution when in an aqueous solution being compatible with said dispersion.
Claim 3
Dependent Claim
27 words
Light-sensitive photographic materials of claim 1 wherein in said hydrophilic coating composition the polymer-in-monomer solution droplets obtained after dispersion have a diameter between 1 and 6 micron.
Claim 4
Dependent Claim
33 words
Light-sensitive photographic materials of claim 1 wherein in said hydrophilic coating composition the water-soluble filmforming polymer is polymethyl methacrylate or polystyrene and the water insoluble ethylenically unsaturated monomer is methyl methacrylate or styrene.
Claim 5
Dependent Claim
19 words
Light-sensitive photographic materials of claim 1 wherein said hydrophilic coating composition the hydrophilic colloid is gelatin or polyethylene oxide.
Claim 6
Dependent Claim
34 words
Light-sensitive photographic material of claim 1 wherein said hydrophilic coating composition the dispersing agent has the formula: R--CH.sub.2 --SO.sub.3 Na wherein R is a straight chain alkyl group of 14 to 18 carbon atoms.
Claim 7
Dependent Claim
34 words
Light-sensitive photographic materials of claim 1 wherein said hydrophilic coating composition from 0.1 to 5 percent by weight of water-insoluble film-forming polymer is dissolved with respect to the weight of water-insoluble ethylenically unsaturated monomer.
Claim 8
Dependent Claim
30 words
Light-sensitive photographic materials of claim 1 wherein in said hydrophilic coating composition from 10 to 50 g of hydrophilic colloid is dissolved per 1000 g total weight of the dispersion.
Claim 9
Dependent Claim
27 words
Light-sensitive photographic materials of claim 1 wherein in said hydrophilic coating composition from 50 to 150 g of polymer-in-monomer solution is present per kilogram of the dispersion.
Claim 10
Dependent Claim
40 words
Light-sensitive photographic materials of claim 1 wherein in said hydrophilic coating composition during the dispersion of polymer-in-monomer solution in the aqueous solution of hydrophilic colloid, from 0.1 to 0.9 g of dispersing agent is present per 100 g of dispersion.
Claim 11
Dependent Claim
29 words
Light-sensitive photographic materials of claim 1 wherein in said hydrophilic coating composition during polymerization from 0.4 to 8.0 g of dispersing agent is present per 100 g of dispersion.
Claim 12
Dependent Claim
34 words
Light-sensitive photographic materials of claim 1 wherein in said hydrophilic coating composition from 0.1 to 5.0 percent by weight of polymerization initiator with respect to the weight of waterinsoluble, ethylenically unsaturated monomer is present.
References Cited (Backward Citations)
US2171765A
Cited
US3143532A
Cited
US3110695A
Cited
US3663665A
Cited
US3811924A
Cited
US3784491A
Cited
US3895949A
Cited
US3867153A
Cited
US3856526A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-09 | 1980-11-08 | 1981-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-09 | 1984-11-08 | 1985-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-09 | 1988-11-08 | 1989-05-10 | $7700.00 | Window Closed / Lapsed |